The present invention relates to an image transmission method and apparatus for transmitting an image via a network, and an image transmission system including the apparatus.
An apparatus in which a video camera is connected to a computer equipment, and an image picked up by the video camera is input to the computer equipment has been developed. Also, an image transmission system for transmitting the image input via the video camera to a remote place via a public communication line or a computer network is known. For example, typical applications of such system are a television meeting or conference system and a video mailing system. In the television meeting system, an output image from a video camera is input to a computer equipment, and the image is exchanged via the network. During the meeting, the image is exchanged between a predetermined source and destination.
On the other hand, an image transmission system which exchanges images input from a plurality of video cameras provided in a large number of places to allow transmission of the image showing the state of a remote place is known. In this system, some specific ones of the plurality of video cameras are selected, their images are acquired via a network, and the acquired images are displayed on a monitor screen. This image transmission system is different from the above-mentioned television meeting system in that an image is not always exchanged between a predetermined source and destination. More specifically, in this image transmission system, a user arbitrary selects an image from a video camera that he or she wants to observe, and observes the selected image displayed on the monitor screen.
In such system, since a video camera connected to a computer equipment connected to a network can be remote-controlled via the network, the video camera connected to the computer equipment may be remote-controlled without the knowledge of the owner (or manager) of the computer equipment, and an image picked up by the camera may be willfully observed by a third party, thus violating the privacy of the owner (or manager). Such a problem tends to occur more often when the computer equipment is connected to an open computer network.
The owner (or manager) of the camera cannot prevent an image from being inadvertently observed by a third party since the prior art has no means for confirming who is observing an image picked up by his or her camera.